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Abstract

A device for modifying the surface of an optical element including a laser beam and a laser energy attenuator. The attenuator varies the energy distribution of the laser beam radially of the beam, thereby etching the surface of the optical element in conformance with the varied energy distribution. In one embodiment, the attenuator includes a positive lens-shaped portion with a laser energy absorbing material therein, which results in etching a positive lens shape on the optical element. In a second embodiment, the attenuator includes a negative lens-shaped portion with a laser energy absorbing material therein, which results in etching a negative lens shape on the optical element. End caps for each of the positive and negative shaped portions have planar outer surfaces and the same refractive indexes as those portions, thereby preventing refraction of the laser beam upon its passing through the attenuator. The attenuator can be cooled as it absorbs the energy from the laser.

Other References

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